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The relationship between coronavirus disease 2019 (COVID-19) and intracerebral hemorrhage remains unclear. We herein report a case of severe COVID-19 pneumonia complicated by multiple simultaneous intracerebral hemorrhages (MSICH). The patient died eight days after the episode of MSICH. No apparent coagulopathy was observed; however, extracorporeal membrane oxygenation and anticoagulation might have caused the occurrence of MSICH. Laboratory findings showed hypercoagulability, suggesting that thrombotic etiologies, such as sinus thrombosis or cerebral infarction, might also have caused MSICH. MSICH can occur as a fatal complication of COVID-19, and this should be considered when providing treatment.

Objectives To identify the specific change of white matter integrity that occurs in the brain network related to epileptic activity in patients with mesial temporal lobe epilepsy (MTLE). Methods We recruited 18 patients with MTLE and 18 healthy subjects. In MTLE patients, the remote functional-deficit zone was delineated using fluorodeoxyglucose positron emission tomography as an extratemporal region showing glucose hypometabolism. Using diffusion magnetic resonance imaging tractography, we defined a seizure propagation tract (PT) as a white matter pathway that connects the focus with a remote functional deficit zone. We also used the corticospinal tract (CST) and inferior longitudinal fasciculus (ILF) as control tracts in the hemisphere ipsilateral to the focus. Fractional anisotropy (FA), mean diffusivity (MD), and volume of the tracts were compared among PT, CST, and ILF. Results Tractographic analysis identified the uncinate fasciculus, arcuate fasciculus, and fornix as PTs. A decrease in FA was found in MTLE patients compared with healthy subjects in all tracts, but PTs showed a more significant decrease in FA than did the two control tracts. Although the change in MD was also found in MTLE patients compared with healthy controls, a tract-specific change was not observed. Although white-matter damage was observed in all candidate tracts examined, the integrity of white matter was most significantly decreased in PTs in MTLE. Conclusion The change in white matter integrity occurs specifically in the pathways that connect the focus and remote functional deficit zones in patients with MTLE, i.e., the pathways that are assume to be associated with seizure propagation.

Objective We assessed the temporal–spatial characteristics of ictal direct current (DC) shifts (or infraslow activity) and high frequency oscillations (HFOs) in 16 patients with intractable focal epilepsy. Methods The underlying etiology consisted of cortical dysplasia, glioma, hippocampal sclerosis, and low-grade neuroepithelial tumor in nine, four, two, and one patients, respectively. The median number of analyzed seizure events was 8.0 per patient (range: 2–10). Chronic electrocorticographic recording was performed with (1) a band-pass filter of 0.016–600 Hz (or 0.016–300 Hz) and a sampling rate of 2000 Hz (or 1000 Hz). Results Ictal DC shifts and a sustained form of ictal HFOs were observed in 75.0% and 50.0% of the patients, and 71.3% and 46.3% of the analyzed seizures. Visual assessment revealed that the onset of ictal DC shifts preceded that of ictal HFOs with statistical significance in 5/7 patients. The spatial extent of ictal DC shifts or HFOs was smaller than that of the conventionally defined seizure onset zone in 9/12 patients. Conclusion Both ictal DC shifts and HFOs might represent the core of tissue generating seizures. Significance The early occurrence of ictal DC shifts warrants further studies to determine the role of glia (possibly mediating ictal DC shifts) in seizure generation.

Objective We describe temporal spread imaging (TSI) that can identify the spatiotemporal pattern of epileptic activity using Magnetoencephalography (MEG). Methods A three-dimensional grid of voxels covering the brain is created. The array-gain minimum-variance spatial filter is applied to an interictal spike to estimate the magnitude of the source and the time (Ta) when the magnitude exceeds a predefined threshold at each voxel. This calculation is performed through all spikes. Each voxel has the mean Ta ( ) and spike number (N sp ), which is the number of spikes whose source exceeds the threshold. Then, a random resampling method is used to determine the cutoff value of N sp for the statistically reproducible pattern of the activity. Finally, all the voxels where the source exceeds the threshold reproducibly shown on the MRI with a color scale representing . Results Four patients with intractable mesial temporal lobe epilepsy (MTLE) were analyzed. In three patients, the common pattern of the overlap between the propagation and the hypometabolism shown by fluorodeoxyglucose-positron emission tomography (FDG-PET) was identified. Conclusions TSI can visualize statistically reproducible patterns of the temporal and spatial spread of epileptic activity. Significance TSI can assess the statistical significance of the spatiotemporal pattern based on its reproducibility.

Objective With advanced electroencephalography (EEG) technology, ‘wideband EEG’ ranging from slow shift to high frequency oscillation (HFO) is clinically available to study human epileptogenesis. The purpose of our study is to clarify the relationship between slow shift, HFO and conventional electrocorticographic (ECoG) change. Methods A patient with right temporal lobe epilepsy who underwent presurgical evaluation with subdural electrodes was studied. Slow shift and HFO were evaluated in 16 habitual seizures with wideband EEG technique (bandpass filter of 0.016–600 Hz). Results Upon seizure occurrence in wideband ECoG, negative slow shifts coexisted with HFO (100–300 Hz) in the ictal onset zone in all investigated seizures. The former always preceded HFO and conventional initial EEG changes by mean value of 1.6 and 20.4 s, respectively. The slow shifts and HFOs were observed only in the restricted ictal onset zone. Conclusions In this particular patient, wideband EEG could delineate both ictal slow shift and HFO to define ictal onset zone, and the earliest occurrence of slow shifts may suggest an early role of glia in slow EEG shift generation than neurons. Significance The time difference of the onset between ictal HFO and slow shift may help to understand epileptogenesis.

The clinical implications of enlarged early cortical components of somatosensory evoked potentials in benign adult familial myoclonus epilepsy remain unknown. Somatosensory evoked potentials following electrical stimulation of the median nerve at the wrist were studied in 16 patients with a clinical diagnosis of benign adult familial myoclonus epilepsy (7 men and 9 women; mean age, 51 ± 18 years) and 19 age-matched apparently healthy control subjects (11 men and 8 women; mean age, 49 ± 18 years). Giant somatosensory evoked potentials were observed in 13 of the 16 patients. P25 and N35 amplitudes in the patient group were 11.4 ± 6.1 and 19.2 ± 11.5 μV, respectively, and both were significantly larger compared with those in control subjects (P = 0.008 for P25 and P < 0.0001 for N35). There was a significant positive relationship between age at somatosensory evoked potential examination and N20, P25, and N35 amplitudes, both in the patient and in the control groups (P < 0.05). The linear regression gradient of the N35 amplitude with respect to age was significantly larger in the patient group than in the control group (P = 0.04). Furthermore, regression analysis showed a significant positive relationship between the myoclonus rating scale and age at time of somatosensory evoked potential examination (R = 0.645, P = 0.007). Somatosensory evoked potential amplitude increased with age in patients with benign adult familial myoclonus epilepsy to a greater extent than in the control subjects, which suggests a progressive increase in cortical excitability based on progressive pathophysiology in benign adult familial myoclonus epilepsy.

Patients with relapsing neuromyelitis optica (NMO) showing contiguous long spinal cord lesions extending over three vertebral segments on the MRI and with positive anti-aquaporin 4 antibodies in sera are usually treated with glucocorticoids or azathioprine. However, some NMO patients even after adequate treatments show relapses. Rituximab (anti-CD 20) therapy has recently been reported to inhibit relapses. We used rituximab to treat three NMO patients defined by the revised NMO criteria of Wingerchuk et al, with rituximab for 2 years and 3 months (mean) at an intervals of about nine months. The annualized relapse rate for the 3 patients during the year before rituximab therapy was 4, 5, and 6, respectively, and this decreased to 3, 1, and 0 in the year after therapy. Case 1 showed three relapses after therapy: however, the symptoms and signs of each of the relapses were milder and the patient showed good responses to steroid pulse therapy. One year after therapy, relapses had disappeared in all cases (observation periods; 18, 18, and 9 months, respectively). After rituximab therapy, these NMO patients showed a decreased mean annualized relapse rate (from 5.0 to 0.6) and EDSS score (from 8.7 to 8.0) after rituximab therapy. No adverse effects were seen. We recommend rituximab therapy for NMO patients resistant to other immunosuppressive therapies such as oral glucocorticoid administration introduced after a severe relapse. However, during long term rituximab treatment, attention needs to be given to infections such as progressive multifocal leucoencephalopathy.

We recently reported clinical anticipation in Japanese families with benign adult familial myoclonus epilepsy (BAFME). However, it remains unknown whether clinical anticipation is predominantly associated with paternal or maternal transmission. We investigated the relationship between gender of the transmitting parent and clinical anticipation in nine BAFME families. Clinical anticipation regarding either cortical tremor or generalised seizures was observed in all 12 parent/child pairs (8 mother/child pairs and 4 father/child pairs). Moreover, a higher degree of clinical anticipation was associated with maternal transmission than with paternal transmission (p=0.03). Although a causative gene for BAFME still remains unknown, our finding suggests that BAFME and diseases with unstable expanding repeats, including those in non-coding regions, might share a similar molecular mechanism because such diseases often show clinical anticipation with maternal transmission.

Objective To clarify the clinical features and mechanism of the transience of myoclonus in patients with a transient myoclonic state with asterixis (TMA). Methods We investigated the clinical and eletrophysiological profiles of 6 patients with TMA (age: 84±3 years). During an asymptomatic period, somatosensory evoked potentials (SEPs) were recorded in all 6 patients and motor evoked potentials (MEPs) were examined in 1 patient. SEPs were recorded and jerk-locked back averaging (JLA) was performed in 2 patients while symptomatic. SEPs were also recorded from 8 aged control subjects (age: 68±5 years). Results All TMA patients had mild chronic systemic diseases. During an asymptomatic period, SEP amplitudes were not significantly enlarged in comparison with control subjects, and MEPs were normal. Examination of 2 patients during symptomatic period indicated no enlargement of SEP amplitudes and JLA disclosed a positive spike preceding myoclonic jerks. In one of these patients, the amplitude of the positive spike decreased once myoclonus improved. Conclusion TMA occurred in aged patients with mild chronic systemic diseases. JLA findings and the absence of giant SEPs further support that TMA is a cortical non-reflex myoclonus. In addition, transient hyperexcitability at the primary motor cortex disclosed by JLA correlated well with its transient symptoms.

Recent neuroimaging studies proposed the importance of the anterior auditory pathway for speech comprehension. Its clinical significance is implicated by semantic dementia or pure word deafness. Neurodegenerative or cerebrovascular nature, however, precluded precise localization of the cortex responsible for speech perception. Electrical cortical stimulation could delineate such localization by producing transient, functional impairment. We investigated engagement of the left anterior temporal cortex in speech perception by means of direct electrical cortical stimulation. Subjects were two partial epilepsy patients, who underwent direct cortical stimulation as a part of invasive presurgical evaluations. Stimulus sites were coregistered to presurgical 3D-MRI, and then to MNI standard space for anatomical localization. Separate from the posterior temporal language area, electrical cortical stimulation revealed a well-restricted language area in the anterior part of the superior temporal sulcus and gyrus (aSTS/STG) in both patients. Auditory sentence comprehension was impaired upon electrical stimulation of aSTS/STG. In one patient, additional investigation revealed that the functional impairment was restricted to auditory sentence comprehension with preserved visual sentence comprehension and perception of music and environmental sounds. Both patients reported that they could hear the voice but not understand the sentence well (e.g., heard as a series of meaningless utterance). The standard coordinates of this restricted area at left aSTS/STG well corresponded with the coordinates of speech perception reported in neuroimaging activation studies in healthy subjects. The present combined anatomo-functional case study, for the first time, demonstrated that aSTS/STG in the language dominant hemisphere actively engages in speech perception.

To assess clinical usefulness of ictal direct current (DC) shifts and also high frequency oscillations (HFO) for delineating epileptogenic zone in human partial epilepsy, we analyzed subdurally recorded EEG in 16 patients, and correlated the findings with pathology. 4, 9, 1 and 2 patients had the diagnosis of glioma, focal cortical dysplasia, low grade neuroepithelial tumor and hippocampal sclerosis, respectively. As the results, ictal DC shifts occurred in 75%, and ictal HFO in 44% of patients. 2 patients with glioma accompanied with focal cortical dysplasia showed ictal DC shifts and ictal HFO with good reproducibility. Ictal DC shifts occurred earlier than or as early as ictal HFO. Both of ictal DC shifts and HFO or either occurred in more restricted areas than conventional ictal changes. We conclude that both ictal DC shifts and HFO finally complementarily contributed to delineate core epileptogenic zone. Earlier occurrence of ictal DC shifts than HFO suggests an active role of glia in seizure generation. A tendency of ictal DC shifts and HFO to occur more in glioma with focal cortical dysplasia may reflect decreased threshold for abnormal depolarization of pyramidal neurons due to glial dysfunction.

The objective was to clarify the clinical and EEG characteristics of ictal paresis. 5 patients developed ictal paresis without loss of awareness: 4 patients showed monoparesis of the upper limb, and 1 hemiparesis. Paresis was mild (MMT 3–4) in all patients. Somatosensory aura in the same limb preceded the paresis in 2, and mild tremulous movements intermittently occurred during ictal paresis in 3. The duration of the paresis varied among patients, ranging from several minutes to 10 days (status epilepticus). All patients had a parietal lesion contralaterally that involved the postcentral gyrus. Ictal EEG changes started from the centroparietal region contralateral to the paresis in 4 patients (as PLEDs in 1). In summary, mild weakness seemed to be characteristic of ictal paresis. It is also suggested that, in the presence of a lesion in the primary somatosensory cortex, epileptic activity at the sensorimotor area gave rise to at least activation of the inhibitory descending system in association with excitatory descending system, and resulted in ictal paresis of the corresponding limb. Concomitant ictal positive motor phenomena (tremulous movements) further support involvement of the excitatory, primary sensorimotor area during ictal paresis.